I think my favorite line (there are lots of good lines in the series) is:
“Blood Feast Island Pansy. Which is your new name until you earn the right to kill.”
Another good one was from the ol’ drippy episode:
Meatwad: He was my best friend!
Master Shake: Yeah? Well then you should know something. When he was pushing me, he mentioned something about not liking you.
Look at me – I’m Shaun Cassidy!
“I do not want to do anything illegal here, but I would kill somebody in front of their own mama to get a ten speed and if anybody testifies against me, I’ll gouge their eyes out.”
Beware The Gorgotron! He’s in love. Shoot 'im in the head!!
My favorite has to be when Billy Witch Doctor has them repeat the “I Am Sofa King We Todd Ed” joke.
Hohoho you say funny thing. 
Shake on his new phone -
“It’s too advanced to be compatible with anything else!”
This gets used quite a bit.